An automatic shading electric welding lens comprises a view window and a side frame. The view window is composed of an optical filter and a liquid crystal sheet sequentially overlapped. The automatic shading electric welding lens is provided with an illuminating device. The illuminating device includes a lighting body, a switch and a power supply electrically connected to each other to form a loop. The lighting body is arranged on a surface of the side frame facing a welding object. The lighting body is a light emitting diode. The switch is a time-delay switch.